The present invention relates generally to operations performed and equipment utilized in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides pressure and temperature measurement in such wells.
Pressure and temperature measurement in wells has generally been accomplished using pressure and temperature transducers which utilize separate pressure and temperature sensors. For example, a transducer may include a piezoelectric pressure sensor and a thermocouple temperature sensor.
Unfortunately, however, most methods of measuring pressure are sensitive to changes in temperature. If the temperature changes relatively rapidly, as happens many times during typical well operations, such as drill stem testing, gravel packing, etc., then it may be very difficult to accurately measure pressure in the well. For example, for the transducer described above, the thermocouple and the piezoelectric crystal may have different temperature change response rates and/or may be located in different positions in the transducer, so that the temperature indicated by the thermocouple is not necessarily the temperature of the piezoelectric crystal.
Therefore, it would be highly desirable to provide a method of measuring pressure in a well in which accuracy of the measurement is improved. The ability to eliminate the contribution of temperature change to the pressure measurement would be very advantageous.